8 4Potassium sulfate is the salt produced when sulfuric acid is neutralised by potassium hydroxide solution. The correct amount of potassium hydroxide solution must be added to neutralise all of the sulfuric acid. Plan an experiment to obtain pure crystals of potassium sulfate from sulfuric acid and potassium hydroxide solution. are provided with common laboratory apparatus. You ........................................................................................................................................................... ........................................................................................................................................................... ........................................................................................................................................................... ........................................................................................................................................................... ........................................................................................................................................................... ........................................................................................................................................................... ........................................................................................................................................................... ........................................................................................................................................................... ..................................................................................................................................................... [6] [Total: 6] Permission to reproduce items where third-party owned material protected by copyright is included has been sought and cleared where possible. Every reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the publisher will be pleased to make amends at the earliest possible opportunity. To avoid the issue of disclosure of answer-related information to candidates, all copyright acknowledgements are reproduced online in the Cambridge International Examinations Copyright Acknowledgements Booklet. This is produced for each series of examinations and is freely available to download at www.cie.org.uk after the live examination series. Cambridge International Examinations is part of the Cambridge Assessment Group. Cambridge Assessment is the brand name of University of Cambridge Local Examinations Syndicate (UCLES), which is itself a department of the University of Cambridge. © UCLES 2016 0620/62/M/J/16 8 4 Calcium carbonate and kaolinite are both white solids found in sedimentary rocks. Calcium carbonate reacts with dilute hydrochloric acid to form aqueous calcium chloride. Kaolinite does not react with dilute acids. You are provided with a mixture of calcium carbonate and kaolinite and access to dilute hydrochloric acid. Plan an experiment to determine the percentage by mass of calcium carbonate in the mixture. ........................................................................................................................................................... ........................................................................................................................................................... ........................................................................................................................................................... ........................................................................................................................................................... ........................................................................................................................................................... ........................................................................................................................................................... ........................................................................................................................................................... ........................................................................................................................................................... ........................................................................................................................................................... ..................................................................................................................................................... [6] [Total: 6] Permission to reproduce items where third-party owned material protected by copyright is included has been sought and cleared where possible. Every reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the publisher will be pleased to make amends at the earliest possible opportunity. To avoid the issue of disclosure of answer-related information to candidates, all copyright acknowledgements are reproduced online in the Cambridge International Examinations Copyright Acknowledgements Booklet. This is produced for each series of examinations and is freely available to download at www.cie.org.uk after the live examination series. Cambridge International Examinations is part of the Cambridge Assessment Group. Cambridge Assessment is the brand name of University of Cambridge Local Examinations Syndicate (UCLES), which is itself a department of the University of Cambridge. © UCLES 2017 0620/62/M/J/17 9 4 Aqueous solutions of barium hydroxide are alkaline. Plan an investigation to find the concentration of an aqueous solution of barium hydroxide. You are provided with an aqueous solution of barium hydroxide, dilute hydrochloric acid of known concentration and common laboratory apparatus. ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ...................................................................................................................................................... [6] [Total: 6] © UCLES 2018 0620/62/M/J/18 [Turn over 9 4Azurite is an ore of copper which contains copper(II) carbonate. Azurite contains no other metal ions. Plan an experiment to show how a sample of copper could be obtained from large lumps of azurite. answer should include: Your ●● ●● escriptions of the reactions involved d the expected observations. You are provided with a large lump of azurite and common laboratory chemicals and apparatus. ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ...................................................................................................................................................... [6] © UCLES 2019 0620/62/M/J/19 [Turn over 11 4Many window-cleaning products contain aqueous ammonia. Aqueous ammonia is an alkali that reacts with dilute acids. Plan an investigation to find which of two window-cleaning products contains the most concentrated aqueous ammonia. Include in your plan: ●● the method you will use ●● how your results will be used to determine which window-cleaning product contains the most concentrated aqueous ammonia. You are provided with an aqueous solution of the two window‑cleaning products, dilute hydrochloric acid of known concentration and common laboratory apparatus. ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ...................................................................................................................................................... [6] © UCLES 2020 0620/62/M/J/20 [Turn over 11 4The mineral epsomite contains hydrated magnesium sulfate. When epsomite is heated strongly, it loses water and eventually becomes anhydrous magnesium sulfate. Plan an investigation to find the percentage by mass of water in a sample of epsomite. Your plan should include how you would calculate the percentage by mass of water in epsomite. You have access to common laboratory apparatus. ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ...................................................................................................................................................... [6] © UCLES 2021 0620/62/M/J/21 [Turn over 9 4Metal rings can be coated with a layer of copper using electricity. Plan an experiment to electroplate a small metal ring with copper. You are provided with common laboratory apparatus, a copper rod, copper(II) sulfate crystals, water and a small metal ring. Include a labelled diagram in your answer. ........................................................................................................................................................... ........................................................................................................................................................... ........................................................................................................................................................... ........................................................................................................................................................... ........................................................................................................................................................... ........................................................................................................................................................... ........................................................................................................................................................... ........................................................................................................................................................... ........................................................................................................................................................... ..................................................................................................................................................... [6] [Total: 6] © UCLES 2016 0620/62/O/N/16 [Turn over 8 4When iron nails rust, the mass of the nails increases. Plan an experiment to investigate if iron nails rust more quickly in tap water or in distilled water. You are provided with new iron nails and common laboratory apparatus. ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ...................................................................................................................................................... [6] [Total: 6] Permission to reproduce items where third-party owned material protected by copyright is included has been sought and cleared where possible. Every reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the publisher will be pleased to make amends at the earliest possible opportunity. To avoid the issue of disclosure of answer-related information to candidates, all copyright acknowledgements are reproduced online in the Cambridge International Examinations Copyright Acknowledgements Booklet. This is produced for each series of examinations and is freely available to download at www.cie.org.uk after the live examination series. Cambridge International Examinations is part of the Cambridge Assessment Group. Cambridge Assessment is the brand name of University of Cambridge Local Examinations Syndicate (UCLES), which is itself a department of the University of Cambridge. © UCLES 2017 0620/62/O/N/17 9 4When solid C and solid D separately react with dilute hydrochloric acid, one reaction is exothermic and one reaction is endothermic. Plan an investigation to determine: ●● ●● hich reaction is exothermic and which reaction is endothermic w which energy change is greater. You are provided with solid C and solid D, dilute hydrochloric acid and common laboratory apparatus. ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ...................................................................................................................................................... [6] [Total: 6] © UCLES 2018 0620/62/O/N/18 www.egyptigstudentroom.com www.egyptigstudentroom.com [Turn over 9 4 The table gives some information about the properties of three substances found in a hand cream. substance reaction with dilute nitric acid polystyrene beads no reaction calcium carbonate reacts and dissolves sodium fluoride dissolves se the information in the table to plan an experiment to obtain a pure, dry sample of U polystyrene beads from this mixture of substances. You are provided with a mixture of the three substances and common laboratory apparatus. ........................................................................................................................................................... ........................................................................................................................................................... ........................................................................................................................................................... ........................................................................................................................................................... ........................................................................................................................................................... ........................................................................................................................................................... ........................................................................................................................................................... ........................................................................................................................................................... ........................................................................................................................................................... ..................................................................................................................................................... [6] © UCLES 2019 0620/62/O/N/19 [Turn over 9 4Brass is a mixture of two metals, copper and zinc. opper does not react with dilute sulfuric acid. Zinc reacts with hot dilute sulfuric acid to form the C soluble salt zinc sulfate. lan an investigation to find the percentage by mass of zinc in a sample of brass. P In your answer you should include how to calculate the percentage by mass of zinc. You have access to normal laboratory apparatus. © UCLES 2020 0620/62/O/N/20 [Turn over 10 4 Cobalt is a metal. Cobalt is between copper and iron in the reactivity series. The mineral spherocobaltite contains the compound cobalt(II) carbonate and no other metal ions. Cobalt(II) carbonate is insoluble in water and reacts with dilute acids to form an aqueous solution of a salt. escribe how you would obtain a sample of cobalt metal starting with a large lump of spherocobaltite. D You have access to all normal laboratory apparatus and chemicals. ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ...................................................................................................................................................... [6] © UCLES 2021 0620/62/O/N/21 8 4 The diagram shows some coffee beans. Caffeine occurs naturally in coffee beans. Caffeine is a white crystalline solid. It is very soluble in hot water but much less soluble in cold water. Plan an investigation to obtain a pure crystalline sample of caffeine from coffee beans. Assume that all other soluble substances in coffee beans are very soluble in both hot and cold water. You are provided with coffee beans and common laboratory apparatus. ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ...................................................................................................................................................... [6] © UCLES 2022 0620/62/M/J/22 9 4Hydrogels are powders that absorb water to form hydrated solids. Hydrogels and the hydrated solids formed are insoluble in water. Plan an investigation to find which hydrogel, hydrogel A or hydrogel B, is able to absorb the greater mass of water. You are provided with samples of hydrogel A, hydrogel B, water and common laboratory apparatus. ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ...................................................................................................................................................... [6] © UCLES 2022 0620/62/O/N/22 [Turn over 11 4 admium, cobalt and vanadium are all metals. They react with dilute hydrochloric acid to form C hydrogen gas. These reactions are exothermic. Plan an investigation to find the order of reactivity of the three metals. Your plan must make it clear how your investigation will be a fair test and how you will use your results to place the metals in order of reactivity. ou are provided with powdered samples of each metal, dilute hydrochloric acid and common Y laboratory apparatus. ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ............................................................................................................................................................ ...................................................................................................................................................... [6] © UCLES 2023 0620/62/F/M/23 [Turn over
